I've had the same problem. I eventually managed to find some on this website: www.easycactus.co.uk . They weren't very expensive and although they weren't very big, they gave me 3 instead of the 2 that I paid for. Hope that helps!

Although spineless varieties are easier than those with you dont have to exclude them from your collection.

In fact dont be fooled into thinking no spines no pain......... as most cacti have little hair like glochlids that are more easy to get stuck in you than the more visible spines.

I use Opuntia robusta and O,Ficus indica ,these 2 grow very quickly and the tortoises enjoy the new pads, some people burn the spines/glochlids and others rub them off . And others feed as they are with no problem. I use a mix of the first 2 .

Another smaller variety is the O,elata or O,englammani or O,conchellia, these in fact have relativly small amounts of spines and next to no glochlids.

All the species named so far will cope with our cold weather if kept dry in the winter.

Another slower grower but with no spines is the Opuntia falcata (now known as Consolea falcata) this one is also enjoyed but is probably more suited to display and occasional harvest than a regular feeder. Also to my cost i lost approx £100 worth last winter in the greenhouse,the plants were killedby the temp........hardly suprising as i now know they originate from Haiti.

Pic 1 is Opuntia ficus indica on left and robuta on right
Pic 2 is opuntia falcata